Telephone-exchange system.



H. P. CLAUSEN & C. L. GOODRUM. TELEPHONE EXCHANGE SYSTEM.

APPLICATION FILED APR.21. 1916.

1 ,25'6,500. Patented Feb. 12, 1918.

2 SHEETS-SHEET 1.

lm/enforsz Henry 1? Clause/7. Char/es L. Good/um.

H. P. CLAUSEN & C. L. GOODRUM.

TELEPHONE EXCHANGE SYSTEM.

APPLICATION FILED APR.27. 1916.

1 56,500. Patented Feb. 12, 1918.

2 SHEETS-SHEET 2.

ln ven'fors: Henry F. (Vac/sen, (hair/e5 Good/um.

' ing line.

HENRY P. CLAUSEN,

n are.

OF MOUNT VERNON, AND CHARLES L. GOODRUM, OF NEW YORK,

N. Y., ASSIGNORS TO WESTERN ELECTRIC COMPANY, INCORPORATED, OF NEW YORK,

N. Y., A CORPORATION OF NEW YORK.

TELEPHONE-EXCHANGE SYSTEM.

Specification of Letters latent.

Patented Feb. 1 2, 31838..

Application filed April 27, 1916. Serial No. 93,875.

.useful Improvements. in Telephone-Exchange Systems, of which the following is a full, clear, concise, and exact description.

This invention relates to telephone exchange systems of the type in wh1ch auto'- matic switching means are employed in the operation of connecting the lines of two subscribers together through an exchange and more particularly to systems of this class equipped with the two-wire multiple type of circuits.

The object of this invention is to provide simple and efficient means in such equipments whereby the operation of a line finder switch in hunting for a calling line will be inaudible to busy lines multipled to the same group.

In accordance with this invention, means are provided for causing the line finder to move to position for its brushes to engage the calling line without the use of a test potential on the brushes of the finder. This may be accomplished by the use of an auxiliary switching means common to the line finders of one group, which operates in response to a call on a line of that group to determine the movement of a line der which will connect its brushes with the call- The auxiliary switching means may comprise a pair of switches, one for controlling the rotary movement of the line finder, the other to control the vertical movement of the finder. These switches may be controlled from the line and cutoff relays.

In the drawings Figures 1 and 2 combined by placing Fig. 1 above Fig. 2, show diagrammatically the apparatus and connections of a portion of a telephone exchange equipment embodying the features of this invention.

Fig. 1 shows a plurality of telephone line circuits and two line finder switches therefor, there being in practice ten of these finder switches for every hundred lines,

each switch being provided with a hundred switchhook 6 in the usual manner.

pairs of contacts and each line being multipled to all of the switches. The line finder switches may be of any well-known type of two-movement switch, "the one shown for convenience in this drawing being similar to that disclosed in Patent No. 1,252,420, to O. F. Forsberg, patented January 8 1918, and assigned to the same assignee. In this particular switch there are a hundred pairs of contacts arranged in vertical groups of ten pairs each and ten sets of brushes arranged spirally around a shaft which is adapted to be moved in rotary and vertical directions to bring a pair of brushes into engagement with any pair of contacts in its associated group. Each finder switch has a motor mechanism for moving the brushes to the desired position. an escapement mechanism controlling a private or side switch, and a release mechanism.

In Fig. 2 there are shown three switches, two of which may be of the ordinary rotary type having a Zero or normal position and a release mechanism, the other being of a type adapted to rotate continuously in one direction. There will be one each of the switches shown on Fig. 2 for every group of ten of the line finder switches such as are shown on Fig. 1.

Referring to the drawings, and particularly to Fig. 1, it will be noted that the telephone lincs are arranged in groups A and B, and that there are provided two line finder switches C and D to the contacts of which'the lines of the two groups are multipled, the same line of each group being connected with contacts in the same level of each of the line finder switches.

Referring now to the operation of the system, it will be assumed that the party at substation 5 desires to make a call which he will do byremoving his receiver from the Closure of the switchhook contact 7, will complete a circuit for the line relay 8 from battery 9, through normally closed contacts 10 and 11 of cut-off relay 12 and over the line wires 13 and 14 of the subscribers circuit. The energization of the line relay 8 closes contacts 15 and 16. The closure of contact 16 completes a circuit for a group-control relay 17 common to the group of lines in which the line of subscriber 5 is located. The circuit for the group-control relay 1'! teries 42 and 43. energizes the relay 36 and the interrupter will be from battery 18, through contact 16 of the line relay, over wire 13 and back contact 10 of cut oil relay 12 to ground at 19 of the battery 9. The energization of the relay 17 closes contacts 20 and 21, the closure of contact 20 grounding switch contact 23 adapted to be engaged by a brush 24 of a rotary switch 25. The closure of contact 21 of the group-control relay 17 completes a circuit which may be traced from ground, through a normally closed contact 27 of a relay 28 associated with an allotter switch 29, over conductor 30, through contact 21 of the group-control relay 17 over conductor 31, through normally closed contacts 32 and 33 of group-control magnets 34 and 35, and through a parallel path including a slowrelease relay 36, an interrupter magnet 37 and a contact 38 of motor magnet 39 to bat- Current in these paths magnet 37, the energization of the interrupter magnet 37 closing a contact 40 and completing a circuit for the motor magnet 39. The motor magnet 39 after it operates will open the contact 38 and close a contact 41, the opening of the contact 38, causing the deenergization of the interrupter magnet 37 thereby opening the circuit of the motor magnet 39 to again close the circuitof magnet 37, the operation being repeated to cause said motor magnet to intermittently open and close its contacts 38 and 41. The clo sure of contact 41 will complete a circuit for a motor magnet 45 (shown on Fig. 1), which controls the rotary movement of a shaft 46 carrying spirally arranged brushes 47, 47 and 48, 48 of the line finder switch C. The circuit of this rotary magnet may be traced from battery at 50, through the winding of the rotary magnet 45, over conductor 51, through a brush 52 of an allotter switch 53, over conductor 54 and through contact 41 of motor magnet 39, to ground at 55. At the same time there will be completed a circuit fora slow-release release-controlling magnet 56 for the line finder switch C, which circuit may be traced from battery 57, through the side-switch arm 58 and to ground at 55 over the same path as just traced for the rotary magnet 45. Each closure of the contact 41 of the motormagnet 39 will cause one step of the rotary switch 25, and one operation of the rotary magnet 45 of the line finder switch C, and this rotary movement will continue until the brush 24 of the rotary switch 25 engages a contact 23 connected with ground, which in this particular case is the first contact of the switch. When this occurs, there will be completed an energizing circuit from battery 60, through the winding of a shift magnet 61 over conductor 62, brush 24 and contact 23 of rotary switch 25, over conductor 63, through the contact 20 of the group-control relay, to ground. The energization of this shift magnet 61 closes a contact 64 which shifts the energizing circuit from the motor mechanism of the switch 25 to the motor mechanism of a rotary switch 66, the brush 67 of which is connected with ground. Upon the closure of contact 64 there is completed a circuit'for an interrupter relay 68 for a motor magnet 69 of the switch 66 to cause the rotation of said switch 66, this circuit being from battery through winding of interrupter relay 68, contact 77 of magnet 69, conductor 88, conductor 89, contact 64 of shift magnet 61, contacts 33 and 32' of group control relays 35 and 34, conductor 31, contact 21 of group control relay 17, conductor 30, contact 27 to ground. As the motor magnet 69 operates, it closes contact 70 which completes a circuit for the vertical magnet 71 of the line finder switch 0, which circuit may be traced from battery 50, through the winding of the vertical magnet 71 over conductor 72, through brush 73 of the allotter switch 53, over conductor 74 and through contact 70, to ground at 7 5. Each interruption of the circuit of the motor magnet 69 by the operation of the interrupter relay 68 will cause one step of the rotary switch 66 and one Vertical step of the line finder switch C, this continuing until the brush 67 of the switch 66 reaches a contact 76 of said switch which has a circuit which is controlled through contact 15 of the line relay 8. When this point is reached, there will be completed a circuit for the group-control relay 34 which may be 7 traced from battery 78, through a brush 79 of the rotary switch 25, through contact 80 of this switch, over conductor 81, through contact 15 of the line relay, over conductor 82, through winding of the group-control relay 34, conductor 83, contact 76 and brush 67 of the rotary switch 66, to ground at 84. This will energize the relay 34 and open its contact32, thereby opening the circuit over which the motor magnets of the switches 25 and 66 receive their operating current. The opening of contact 32 will also open the circuit of the slow-release release-controlling magnet 36, which when it is denergized, will close contact thereby completing a circuit for the release magnets 86 and .87, controlling respectively the release of the switches 25 and 66.

Associated with each of the line finder switches C and D, is an escapement magnet 90, the operation of which controls sides'witch brushes 58, 91, 92 and 93. The escapement magnet associated'with the line finder switch C is first energized over a circuit which may be traced from battery 95, through the winding of the escapement magnet 90, over conductor 96 through a contact and brush 97 of the allotter switch 53, over conductor 98., through the contact 64' of the shift magnet 61, through contacts 33 and 32 of the group-control magnets 34: and 35,

conductor 31, through contact 21 of the group-control relay 17, over conductor 30 and through contact 27 of the relay 28, to ground. This energization of the escapeinent magnet 90 will occur first upon the operation of the shift magnet 61 and will cause the side-switch brushes 58, 91, 92 and 93 to moveinto their second position. Upon the operation of the roup-control relay 34, thecircuit just trace will be opened at the contact 32, causing the de'e'nergization of the cscapement magnet 90 which will cause the side-switch brushes 58, 91, 92 and 93 to be moved into their third position. When moved into this position the side-switch brush 91 will complete a circuit for a motor magnet 99 of the allotter switch 53, this circuit being traced from battery 100 through the winding of the motor magnet 99, over conductor 101, through brush 102 of the allotter switch, over conductor 103, through the third contact and brush 91 of the side switch, to ground at 10 1. This will cause the movement of the allotter switch brushes until the brush 102 strikes a contact which is not grounded by a side switch arm of a finder switch, at which point the brushes 52 and 73 of the allotter switch will be in position to complete a circuit through an idle line finder switch when the switches 25 and 66 are again operated in response to a call.

What is claimed is:

1. In a telephone exchange system of the two-wire multiple type, telephone lines terminating at said exchange, automatic switching devices operated to complete connection with said telephone lines, contacts on said switches in which said lines terminate, movable brushes on said switches normally free from potential, adapted to have a rotary and vertical movement into engagement with said lines, and switching means common to a plurality of said switching devices and controlled in the operation ofmaliing a call to control the movement of said brushes into engagement with the contacts of the calling line. i

2. In a telephone exchange system of the two-wire multiple type, telephone lines terminating at said exchange, line relays for said lines, automatic switches operated to complete connections with said lines, contacts on said switches in which said lines terminate, movable brushes on said switches normally free from potential adapted to be moved into engagement with the contacts of a calling line, switching means common to a plurality of automatic switches for controlling the movement of said brushes into engagement with thecontacts of a calling line and a controlling circuit for said switching means controlled by the line relay of the calling line. 1

In a telephone exchange system of the two-wire multiple type, a lurality of calling lines terminating at sai exchange, automatic switches, contacts on said switches in which said lines terminate, brushes for said switches normally free from potentialhaving a rotary and vertical movement into ngagement with said contacts and a pair of switches common to a plurality of said automatic switches and controlled over the calling line for controlling the rotary and vertical movement of said brushes into engagement with the contacts of the calling line.

4. In a telephone exchange system, a. plurality of line circuits terminating at the exchange, a plurality of two-movement .line finder switches including movable brushes normally free from potential for completingconnection with a calling line, and apair of switching devices common to a plurality of said line finder switches and controlled over a calling line for separately controlling the two movements of said line finder switch.

5. In a telephone exchange system, a plurality of line circuits terminating at the exchange, a plurality of two-movement line finder switches including movable brushes normally free from potential for completing connection with a calling line, and a pair of switching devices common to a plurality of said line finder switches and controlled over said line wires, one of said switching devices controlling one movement of said line finder switch and the other ofsaid switches controlling the other movement of said line finder switch.

6. In a telephone exchange system, a plurality of line circuits terminating at the exchange, line finder switches, brushes normally free from potential thereon adapted to have rotary and vertical movements into 105 engagement with a calling line, a pair of switch controlling devices common to a plurality of said line finder switches, one of said switch controlling devices being adapted to control the rotary movement of said line finder switch, the other of said switch; controlling devices being adapted tocontrol the vertical movement of said line finder switch, and means controlled over a calling line for controlling the operation of said switch controlling devices.

7. In a telephone exchange system, aplurality of line circuits terminating at the exchange, a plurality of line finder switches including movable brushes normally, free from potential each adapted to have rotary and vertical movements into engagement with a calling line, rotary and vertical magnets for controlling the movement of said line finder switch, circuits therefor, and a pair of automatically operating circuit controlling devices common to a plurality of said line finder switches and controlled over a calling line for separately controlling the circuits for said rotary and vertical magnets.

8. In a telephone exchangesystem, a plurality of line circuits terminating at the exchange, a line relay associated. with each of said lines, line finder switches common to a plurality of said lines, sets of brushes normally free from potential for each of said switches having rotary and vertical movements into engagement with a corresponding line, rotary and vertical controlling magnets for said line finder switches, circuits for said magnets, circuit controlling switches for said magnet circuits common to a plurality of line finder switches, and means controlled by the operation of a line relay associated with any calling line for causing the operation of said circuit controlling switches to connect brushes of a line finder switch with the conductors of the calling line.

9. In a telephone exchange system, a plu rality of line circuits terminating at the exchange, line finder switches common to a plurality of said lines, sets of brushes normally free from potential for each of said line finder switches having rotary and vertical movements into engagement with terminals of a calling line, rotary and vertical magnets for controlling the movement of said brushes, circuits for said magnets, a pair of electrically-operated circuit controlling devices common to the circuits of a plurality of said line finder switches for controlling the rotary and vertical movement thereof, one of said circuit controlling devices being adapted to control the rotary movement'of said line finder switches, the other being adapted to control the vertical movement of said line finder switches, and circuit means and connections controlled by the line relay of the calling line foicseparately operating said circuit controlling devices to control the rotary and vertical movements respectively of said line finder switch.

10. In a telephone exchange system, a plurality of line circuits terminating at the exchange, a line finder switch including movable brushes normally free from potential at the exchange having step-by-step rotary and vertical movements, rotary and vertical magnets for controlling the two movements of said switch, circuits for said magnets and a pair of circuit-controlling devices common to a plurality of said line finder switches, each of said circuit-controlling devices being adapted to be separately operated, one to control the impulses through the rotary magnets of the line finder switches, the other to control the impulses through the vertical magnets of the line finder switches and means controlled over the calling line for controlling the operation of said circuit-controlling devices.

In witness whereof, we hereunto subscribe our names this 26th day of April A. D., 1916.

HENRY P. CLAUSEN. CHARLES L. QOODRUM. 

